Solvation and rotational relaxation of coumarin 153 and 4-aminophthalimide in a new hydrophobic ionic liquid: Role of N-H…F interaction on solvation dynamics

► Time-resolved fluorescence of coumarin 153 and 4-aminophthalimide have been studied. ► Hydrophobic room-temperature ionic liquid has been used for the study. ► Average solvation time is found to depend on the probe molecules. ► Solute-solvent specific interaction is found to play an important role.